Common Defects: Smoke & CO Detectors

Nearly every house I inspect contains either too few smoke and carbon monoxide detectors or old detectors that aren’t working. In this post we’ll go over where to locate these important safety devices and how to properly maintain them.

Smoke and carbon monoxide (CO) detectors are often taken for granted. In fact, many people view smoke alarms as more of an annoyance than a help because they tend to go off when smoke comes out of the kitchen while cooking, causing that unwanted loud beep at the worst possible time. It’s easy to forget that the same loud beep that is so annoying in the middle of preparing a meal has the ability to wake us from a deep sleep if a real emergency occurs. So, yes, these detectors are, in fact, important and should never be taken for granted!

In recent years, combination “2-in-1” detectors that detect both smoke and carbon monoxide have become very popular. While these units are not “bad” and are certainly better than having no detectors at all, it is actually more ideal to have separate detectors that each detect one hazard or the other. Smoke rises quickly, so smoke alarms are ideally located on the ceiling. In fact, you will rarely, if ever, see them anywhere else. Carbon monoxide, on the other hand, is best detected about 5 feet from the ground. Depending on how much carbon monoxide is in the air (measured in part per million, or “ppm”), it could really make a difference having the detectors located several feet below the ceiling.

So where should these detectors be located? The general rule for both types of detectors is that they be placed on each floor, in each sleeping area, in garages, and near sources of combustion (fireplaces, furnaces, etc.). I often see at least smoke detectors in hallways, but rarely in bedrooms, and I often don’t see CO detectors at all. The reason they are recommended in every sleeping area (bedroom) is so everyone in the family can hear the alarms and be alerted if they’re asleep. Carbon monoxide detectors are especially important in houses that contain attached garages and several combustion sources, but even houses without these can contain some carbon monoxide.

Maintaining your smoke and CO detectors is every bit as important as having them. While they can be hardwired, most homes contain battery powered units and the batteries will obviously die over time. Check the manufacturer’s recommendations for testing your alarms, and schedule periodic tests to ensure they are working properly. Periodic testing is very important to avoid non-working units that can’t do their job if and when an emergency occurs.

So stay on top of your smoke and CO detectors and install them in all recommended locations. And don’t forget to reinsert the battery for the detector you quickly silenced while cooking that last steak on the stove!

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Author: hillinspections

I am a Certified Master Inspector (CMI) and the owner and operator of Hill Property Inspections LLC, the top-rated inspection company in the greater Johnstown, PA area, based out of western Pennsylvania. I specialize in property inspections and environmental testing services and have a passion for helping my own clients and other families in learning to properly maintain their homes. I’m also the owner of Hill Pest Control, LLC and a pest management professional committed to helping our clients rid their homes and businesses of unwanted pests. I am an Army veteran, former State Farm Insurance Agent, and real estate investor with experience in all facets of real estate construction, transaction and insurance. I am also the founder and President of the Southwestern PA Chapter of the International Association of Certified Home Inspectors (InterNACHI) and an affiliate member of the Cambria-Somerset Association of Realtors (CSAR).

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